Tube preamp reliability vs SS?

Convenience is a very  legitimate  concern. For me the actual  sound quality and the  music  listening  experience  is the overwhelming criteria for choosing an audio component.

Largely a case of how big your bank account is.

"Would running low freq music, heavy bass techno etc etc through system break in the capacitors at all on preamp? Adding more bass overall???"

A very good question, I really have no idea as to how that might affect the capacitor break in, Al or Ralph might weigh in here. I DO know first hand that teflon capacitors take a while to settle in. NOW getting back to what Charles said about power supplies and how they make a difference, I couldn't agree more and it is something you should also pay particular attention to if you really want that bass to come through naturally and well articulated along with the amp/speaker interface. Power supplies are probably the biggest difference in adding a more effortless, natural and larger presentation of the music without it congealing and sounding too LOUD. They ALSO add to the cost. You might also consider  integrating a quality subwoofer as well for your music of  choice. 

"Musicians love tube amps since tubes are easy to replace. Semiconductors failure is harder to diagnose and usually require professional repair."

Not too sure about that Kijanki.  I would think it's more about the fact that the sound can be manipulated to achieve a desired result. At least that's the case with the one's that I've talked to. Plus most of the guys that use tube amps just like the sound, it gives them that "tube thing" that can't be replicated by SS. 2nd order distortions and all that makes tubes, well tubeelicious :)

Audio reproduction and tube guitar amplifiers have completely different objectives with one similarity, the preference for tubes in the circuit, it's simply a matter of taste. 

Tubegroover, That’s what I heard from the few of them. Nice distortion (crunch) is another reason. It seems logical to me that tech person in the band (often one of musicians) can easily bring amp back to life by simply replacing a tube, but SS amp would be practically irreparable on the road. Any performing musicians here?

Yes, audio amps and guitars amps are different but ability to fix them easily is always appreciated.